Abstract
Vitamin D deficiency has been linked to asthma because of the proposed role of vitamin D in inflammation control and host defense against infection. Antimicrobial peptides (AMPs) are effector molecules of the innate immune system, and their expression may be decreased by allergic inflammation. Vitamin D increases expression of AMP in vitro, but its effects on AMPs levels in asthma patients are unknown.
Hypothesis: AMP levels in nasal secretions of patients with allergic asthma are lower than those in controls and can be restored by vitamin D substitution.
Methods and results: 20 allergic asthma patients and 20 controls (18-45 yrs) were included. The influence of allergic asthma on AMPs was assessed in a case control design, and the effect of 7 days daily oral treatment with 2 mcg 1,25(OH)2D3 active vitamin D (calcitriol) on AMPs was assessed in a placebo-controlled cross-over study.
The levels of the AMPs HNP1-3 and NGAL were significantly lower in asthmatics, whereas there was a trend for LL-37 (table 1).
Table 1. Mean AMP in asthma patients and healthy controls
Treatment with 1,25(OH)2D3 significantly increased HNP1-3 and there was a trend for an increase in LL-37 and NGAL.
Conclusion: Levels of AMPs are lower in nasal secretions in asthmatics, and treatment with active vitamin D increases these levels.
- © 2011 ERS
